High voltage pin socket connector



Nov. 11, 1958 c. J. WATTERS ETAL HIGH VOLTAGE PIN SOCKET CONNECTOR Filed April 26, 1954 a 7 M2 3 a n l "w u 99 32 aw m w m M m a w 3 Q P Inventors: Ham FNieb Wil uhr, clarencetlwatters, by %u&

Their Attorr wey.

United States Patent Office 2,860,316 HIGH VOLTAGE PIN SOCKET CONNECTOR Clarence J. Walters and William F. Niebuhr, Schenectady, N. Y., assignors to General Electric Company, a corporation of New York Application April 26, 1954, Serial No. 425,506 5 Claims. (Cl. 339-89) This invention relates to a pin socket connector structure which is particularly adapted for production in a relatively small size, and more particularly to connectors which are especially adapted for employment with ignition systems which are to be operated under extreme variations of atmospheric pressure and temperature such as are commonly encountered by high altitude aircraft.

Among the major requirements in the production of a pin socket connector such as is adapted for instance for establishing connections to a flexible insulated electrical conductor suitable for use in ignition systems for high flying aircraft arise from the fact that the connector preferably must be capable of operation at voltages as high as ten thousand volts at altitudes as high as sixty thousand feet, at temperatures as high as 500 F., in extremely moist atmospheres, and must at the same time occupy a minimum of space and add a very minimum in weight to the aircraft which it serves.

One of the objects of this invention, therefore, is to employ a superior flexible insulating material as a connector insulator and to provide a moisture-proof insulating bond between the insulator and the insulation of the conductor to which the connector is attached.

Another object is to provide an adequate mechanical connection between the connector insulating member and a conductive terminal socket member which is simple and economical to assemble and disassemble for servicing and which occupies a minimum of space without impairing desired insulating and conductive properties.

Another object is to provide a compact and economical conductive outer covering for the connector structure to provide mechanical protection and electrical shielding which may be simply attached to the connector insulating member and to an insulating cover which may be provided for the conductor to which the connector is attached.

A still further object of the invention is to provide a simple means for attaching a socket connector to a mating pin connector member in the form of a fastening nut and to provide structural means to prevent displacement of the nut by more than a limited amount from the usual assembled position.

Other objects and advantages of this invention will be apparent from the following description and the accompanying drawing.

In carrying out the above objects of this invention in one preferred embodiment thereof a structure may be provided including a pin socket terminal member connected to the end of a conductor, with a tubular insulating member extending over the terminal member and the conductor insulation and being heat bonded thereto. At least one of the insulating or terminal members includes a flange or rib extending into a circumferential groove in the other member.

For a more complete understanding of the invention reference should be made to the following specification and the accompanying drawing in which:

Fig. 1 is a sectional view of a preferred embodiment of the pin socket connector receptacle structure of this in vention.

Fig. 2 is a similar sectional view of an insulated conductive pin structure which is adapted for cooperative engagement with the socket structure of Fig. 1 and which is aligned with Fig. 1 on the drawing to indicate how such engagement would be made.

And Fig. 3 is an enlarged sectional view taken at section 33 of Fig. 1 showing a detail of a preferred socket terminal structure.

Referring more specifically to Fig. 1 there is shown an insulated cable or conductor 10 having a bared conductor end portion 11 from which the insulation has been removed and to which a pin socket terminal 12 has been attached. Surrounding the terminal 12 and the lower insulated end of the conductor 10 is a tubular insulating member 13 and surrounding the insulating member 13 there is a conductive metal shell or ferrule 14.

The terminal 12 is of a tubular structure having a central opening therein for the reception of a connector pin in the lower end thereof. In the upper end of this opening the bared end 11 of the conductor 10 is inserted and fastened preferably by brazing or soldering with a high temperature material such as silver solder.

The structure of the terminal 12 preferably includes the following features. The lower or open end of the terminal body includes a series of axial slots extending from the lower edge thereof indicated at 16 for substantially more than half the length of the terminal member to a point such as indicated at 17. The lower end of this terminal body is thus separated by these slots into a series of axial spring contact fingers, the terminal body being preferably made of a conductive spring material such as a beryllium bronze alloy. Surrounding the body of the terminal member is a sheath 18 which includ:s a lip 19 swaged into a circumferential groove 20 in the main terminal body for retention thereon. Sheath member 18 also includes a lower inwardly extending flange 21 which surrounds and covers and protects the lower ends of the contact fingers formed in the terminal body. The central opening of the flange 21 presents a funnel shape to guide the contact pin as it enters the terminal member. This central opening is of a diameter no greaier than that of the largest pin which is to be inserted into the terminal to prevent the insertion of pins which are too large and to thereby prevent damage to the socket terminal. At an intermediate portion 22 of the contact fingers, the sheath member 18 is formed with a corrugated or crimped shape to provide a reduced inner sheath diameter to thereby back up the spring contact fingers and assist in maintaining the contact pressure even after repeated connections and disconnections have caused appreciable contact wear. This corrugated sheath structure is illustrated by Fig. 3 which is a sectional view, slightly enlarged, taken on section 33 of Fig. 1.

The lower insulated end of conductor 10 and the terminal member 12 are surrounded by the tubular insulating member 13 as stated above. The upper end of the insulating member 13 is preferably heat bonded as indicated at 23 to the outer surface of the insulation of conductor 10. This bond provides a continuous electrical insulation and a moisture seal between these two members. In order to obtain superior insulating qualities the insulating member 13 is preferably composed of polytetrafluoroethylene. A serious problem was encountered in obtaining the desired heat bond between this material and the exterior surface of conductor 10. It has been found however that superior insulating qualities for conductor 10 may be obtained and a satisfactory heat bond can be produced between insulating member 13 and the outer surface of the insulation of conductor 10 if at least the outer covering is also composed of polytetrafluoroethylene material, but Wl'llChaiS only partially cured.

' Production of the above mentioned-heatbond must be accomplished under very. in order to obtain satisfactory results. This is ttue:.because insuffic-ient heating and pressure. will .not produce astrong bond whereas the flow temperature of. this material is-fvery nearly the sameas the softeningv temperature at which a satisfactory-bond can be obtained so that the material may flow away ifover-heatedL It has been found however that satisfactory resultsmay be obtainedbyemployment of:an electrically-heated pairof;hand.pliers.or grippers having internal gripping surfaces .of a..diameter corresponding to the outer diameter of the section of the insulating member 13' which is to be bonded.' However, it has been found .in the production of one embodiment that thepliers or grippers must'be maintained at 710? F. within a tolerance of plus or .minus 10 and a pressure of from three quarters toone andone quarterpounds per squareinchmustbe applied by the grippers to the exterior of the insulating member for a period of 2().to 25 minutes. It will-:be observed thatthe inner surface of the insulating-member 13 includes an inwardly extending flange 24 which fits into a corresponding.circumferential slot 25 in the exterior surface of terminal member .12 in order to maintain the insulating member '13 and .the .terminalmemcarefully controlled: conditions 5 1 assembling nut 34.

be made therebetween. Accordingly, the sheath is preferably expanded as'shown at 36 to surround the upper end of the ferrule 14, and a retaining bushing 37 of a slightly larger diameter is assembled over the sheath in this area to prevent unraveling of the braided structure. The sheath 35, the ferrule 14, and the retaining bushing 37 are then preferably electrically and mechanically uniteclltbya highternperature-brazing or.soldering material such as copper alloy. The retaining bushing 37 preferablyihas. a radiallyoutwardly-extending circumferent-ial flange 38 having: an outer diameter. which is greater than the inner diameter- 0f the flange 33. ofzthe Thus, ;.upon disassembly, the nut 34 cannot be displaced upwardly with respect to the remainder of the assembly-by .morethan the distance to the flange 38. The nut is therefor convenient at all times for its intended use.

.The assembly .of the socket connector. structure, as thus farv described is preferably accomplished in the following manner. The retaining bushing37 and. the assembling nut '34 are slipped over the end of the sheath 35. The sheath '35 is then expanded in diameter as indicated at 36 and the upper end of ferrule 14 is inserted ber 12 in assembled relationship. This relationship is achieved by anexpansio-n and subsequent contraction of the relativelyfiexible insulating member, as will be, more fullydescribed below. This assembly or connection will becharacterizedbelow as a .contraction connection.

''The ferrule member. 14 is maintained in assembled relationship overrthe outside -of the insulating member 13rby cooperation of an. inner shoulder .26 of ,the ferrule with anouter enlarged portion .27 of the insulator member 13. .The. other end of the. enlarged portion 27 is also effectively engaged by the ferrule by means of the following structure. Aretaining bushing 23 is provided which is of a proper. size to fit .between the enlarged portion 27 of the insulator and the adjacent inner portion of the ferrule and having an inwardly extending flange portion .29 which engages the lower end of the enlarged insulator portion 27. Adjacent to. the lower end of this retaining bushing 23, on the inner surface .ofthe' ferrule '14 is a groove in which there is positioned anexpan'sible retaining ring 349 which prevents downward movement of the retaining bushing'28 out of the ferrule, or conversely, prevents upward movement of the ferrule to uncover the retaining bushing and the adjacent portions of the insulating member 13.

A resilient moisture sealing member 31 comprised of a ring "of rubber-like material having a normally unstressed inner diameter slightly smaller' than the cooperating diameter of the insulating member13 is positioned over the insulator member and adjacent to'the retaining bushing. This gasket member'31' is preferably comprised of a material which will withstand extremes of temperature without impairment of its resilient qualities. A suitable material for this purpose has-been 'foundto be a silicone rubber. "At the lower-endofthe ferrule 14 there is providedan exterior circumferential flange 32 which engages an-inner-fiange 33 ofan assemblingnut 34.

In the applications or-installations for which-this connector structure is intended, such as-in ignition systems for aircraft, a metallic radio noise shield is"preferably provided around all conductors. In the case of flexible conductors, this shield is usually in the. form of one or more loose-fitting sheaths which arebraided of small diameter wire. Such a metallic. sheath is shown inthe drawing at. 35. In order to maintainthe shielding effectprovided by the; sheath 3 5. and ferrule .14, a. secure. mechanical. and; electrical ;,c.onnection. must the conductorendll and to complete this portion of the connector.

therein. The nut 34 is then lowered overtheferrule 14 and the bushing 37 is slipped over the expanded portionof sheath '35 below point 36. Ferrule 14, sheath 35 and bushing 37 are then brazed together.

Next, the conductor 10 is 'bared at theend 11. The insulating member 13 is assembled over the conductor 10 to a point such that-the exposed conductor end '11 protrudes at the bottom end of the-insulator -member 13. The terminalsocket member 12-is assembled over -solderedin place. The insu- 13 is thenmoved' downwardly so that the forced over the upper. end portion of theterminal member 12, which has a beveled surface as -shown at--39, and into-the slot 25. It will be noted that this assembly operation requires a slight degree of expansion of the partially resilient insulator member 13. The heatbond is nextmade between the insulating member 13 and'theouter conductor insulation-as described-above. Theconductor 10 is. theninserted upwardly'through ferrule 14-andthreaded through lator member inner rib portion 24 is sheath 35 until the 111811131101 member is brought into The retaining bushing 28, the rethe gasket. 31 are then'assembled If it is necessary to insert the conductor 10 from the upper end of the sheath 35, not shown,;-the lower'end of the sheath 35-may be axially compressedand raised to expose the lower end of conductor 10. The assembly of the insulator member 13, the socket member 12,.and the associated parts may then be made afterthe insertion of conductor 10 into sheath 35.

1 111' Fig. 2 there isshownin section, partially cut away,

.connector: structure; which; may :proyide a; connection .to an jgniter .plug :andmay actually comprise the connector end of such a plug,-or the terminal end of a spark generating apparatus which is to be connected by the conductor 10 to the ignitor. This pin connector structure or assembly includes apin v400i suitable diameter for insertion into the socket terminal member 12 and for providing an electrical connection therewith, an insulator member .41 which maybe composed of a suitable insulating -material such as an insulating ceramic and having an inner diameter larger than the outer diameter of the lower portion of the insulating member 13 to permit insertion therein upon assembly of the socket connector and pin connector structures to thereby theposition shown. taining ring 30- and 0 form a combined interlocking insulation structure having a long minimum surface leakage path to prevent flash-over or surface arcing conditions. It will be seen that linathe assembledrelationship, ,the upper end por- .tionsofthe .pin connector insulator 41 engage ,with the gasket member .31. When,,.thes .as s,en1bli5.. a slfioreed together with suflicient pressure, the gasket 31 therefore provides a moisture-proof pressure seal between the insulator 41 and the insulating member 13. The pressure sealing feature of gasket 31 helps to prevent flash-over at rarified atmospheres encountered by high-flying aircraft.

The pin connector structure also includes an outer metallic conductive shell 42 having exterior threads thereon at 43 for engagement by the assembly nut 34 of the socket connector assembly. By means of this threaded connection, suflicient pressure upon the gasket 31 is assured to provide the moistureproof seal mentioned above.

It will be observed that the retaining bushing 28 and particularly the flange 29 thereof surrounds the insulating member 13 in the axial vicinity of the inwardly extending flange 24 which is in engagement with the slot 25 of the terminal member 12. Thus, the retaining bushing 28, when assembled, effectively prevents any expansion of the insulating member 13 in this vicinity and disengagement of the flange 24 from the slot 25 to maintain the insulating member 13 and the terminal member 12 in positive assembled relationship.

While only one preferred embodiment of the invention has been described and illustrated by way of example in the foregoing, modifications will occur to those skilled in the art and it therefore should be understood that the appended claims are intended to cover all such modifications as fall within the true spirit and scope of the invention.

What We claim as new and desire to secure by Letters Patent of the United States is:

1. A quick detachable connector including a socket assembly and a pin assembly adapted for attachment therewith, said socket assembly including a socket terminal member, a flexible insulated electrical conductor having a bared end connected to said terminal member, a preformed tubular insulating member surrounding said terminal and extending over the adjacent insulated portion of said conductor, said insulating member and at least the outer surface of the insulation of said conductor being comprised of polytetrafluoroethylene and having a heat bonded connection therebetween, said insulating member and said terminal member having an interlocked mechanical connection therebetween, a metallic shielding member surrounding said conductor and said insulator and attached thereto, said pin assembly including a conductive pin adapted for insertion in said socket terminal member and a second tubular insulating member concentrically spaced from and secured to said pin and adapted to surround the portion of said first insulating member covering said socket terminal member when said pin is inserted in said socket terminal member, an annular silicone rubber gasket surrounding said first insulating member and adapted to form a moisture-proof seal with the end of said second insulating member, a second shielding member surrounding said second insulating member, and a threaded attaching nut having a relatively rotatable connection With one of said shielding members and including screw threads for detachable connection to said other shielding member, said other shielding member including screw threads for engagement by said nut.

2. A pin socket connector for an insulated electrical conductor comprising a socket terminal having a central pin-receiving aperture extending therethrough and having a bared end of the conductor secure-d within one end thereof, a tubular insulating member surrounding said terminal member and extending over an insulated portion of said conductor, one of said members including a circumferential slot and the other of said members including a flange extending into said slot for cooperative attachment thereof, said insulating member and at least the outer surface of said conductor insulation being comprised of polytetrafluoroethylene material, at least portions of the adjacent surfaces of said insulation and said insulating member being heat bonded to provide a unitary insulating structure, a substantially rigid bushing member surrounding and mounted on said insulating member in the vicinity of said flange and slot to prevent expansion and disengagement thereof, said insulating member including an outer shoulder in engagement with the side of said bushing member axially positioned away from said terminal, a tubular ferrule of conductive material surrounding said members and including an inner shoulder in engagement with the other end of said outer insulating member shoulder, said ferrule including a groove in the inner surface thereof adjacent to the terminal end of said bushing member, and an expansion retaining ring positioned in said groove to maintain said ferrule and bushing and insulating members in assembled relationship.

3. A pin socket connector for an insulated electrical conductor comprising a socket terminal member having a central pin-receiving aperture extending therethrough and having the bared end of the conductor secured within one end thereof, said terminal member including a circumferential slot in the outer surface thereof adjacent to said conductor connection, a tubular insulating member surrounding said terminal member and extending over an insulated portion of said conductor, said insulating member including a flange on the inner surface thereof extending into said circumferential slot in said terminal member for attachment thereto, said insulating member and at least the outer surface of said conductor insulation being comprised of polytetrafluoroethylene material, at least portions of the adjacent surfaces of said insulation and said insulating member being heat bonded to provide an effectively unitary insulating structure, a substantially rigid bushing member surrounding and mounted on said insulating member in the vicinity of said inwardly-extending flange to prevent expansion of said insulating member and disengagement of said flange from said slot, said insulating member including an outer shoulder in positioned away from said terminal member a tubular ferrule of rigid material surrounding said insulating and bushing members extending flange engaging said ferrule flange, a metallic shielding braid surrounding said conductor and including a central pin-receiving aperture extending therethrough and having a n a i we u e aubst n al i d sh vm m e exp n pn a uisenga em t e said ns lat n surrounding and mounted o f sziid insulaling 'n je mber in, rnen'iber including an'bnter shoulder inengagen ent with t he v' njiiynfifs id fing e and slot. toipreve'nt ,exp'ansipn the, sid fsgnd Bush r nember, axially 'pnsitio ried ay nd -c l,i s enga gen e nt .the r'eof, snid,,insulafi,l g.,mfi,mbfir i11 frqrn d terrrringkn hula; {mule surrqunding s aiid l din anI tq s uu n n e agq 'wi t e idei m mb r iansii ne udin an in mhl i lsi n ne g a mfi l said, bushingmember laiiriallyjposiriqnml away from said with the, glher end of said qu ter insulatinggnleirnber terminal, a. utirbulalrlferrule surrounding ,said members shnulder, ,and,,fasteningmeans,degaehably intercqnnecy andhincluding an inner shnulder in engagement with, the, ingfs aid fe rrule 3 cl bushing member t0 maintain the qtjher end; f sairl in sulating .rnejn lqerfquier shoulder, 'ami ferrulql buliing einglinsuleting n ernbers all in assembled, ia t i ,-m n e fihab y. t somi i n f m 1 i i and bushingmfimber rto rnaint ibefernile, bushing and i u v g gm g s g m a s mbl relation. 1. References Cited mihe file. of rhrs. patent 5 ..A ,pin so ck et .cgniiegrorjdrnan insulated electrical B TEN conductorpenlprisiug a, s ckefl erriiin lmm r hayin 2,294,432 .Weidner Sept. 1, 1942' a entr l. pin-rmii g p lurqlextending here hr u' g 2,397,568 .Se'man A r'.2,."19 416 a d ha ing, ab clJqnd i1h 'conductbnsecured within 2,400,099 Bmba'kr Ma i411914i6 neendiheireof, ,tu l ninsu t ngme q s i g 2,440,190 Aifihan Apnzo, i948 sgicl.,,teII. 1 member, and; ex end ngw v insulated 2,471,468 Weston May 31, .1949 porlionoflsaideqngluctqr,.one ofis gid members including 2,538,808 ;Q 25, 19 51 i ir u i e t a r q li e ot r-of said members i 20 2,540,012 I Siiiati-" 1---. Ian. '30, 1951' eluding a flange extendfng into said .slot for cooperative 2,550,112 Fields Apr. 24,1951 attachment thereof, saidinsulating member andithe outer 2,576,645 1155mm, eial. Nov. 20, 1951 urfa e of d ond c n u u av g l p r- 2,603,682 Ulineet'ilf Jul 15, 1952 tiqns of their adjacent surfacesbonded together toprovide 2,606,849. Dantsizen Aug. 12, 1952 a unitary insulating. strug ture, a. substantially rigid bushing member surrnunding and rnounted bn said insulating FOREIGNPATENTS memberinthe vicinity'of said fla ngeand.slotto preyent 5 3 2. 3 e r n ,--.,-,-:.D 1 

